From: Felix Fietkau <nbd@openwrt.org>
Date: Sun, 13 Jan 2013 08:24:04 +0000 (+0100)
Subject: rework the ubus plugin to support JSON-RPC 2.0
X-Git-Url: http://git.archive.openwrt.org/?p=project%2Fuhttpd.git;a=commitdiff_plain;h=1eedd103be4919683f2d0b2165cefe82b73e4a5f;hp=51da420dfeda783c74f5a3d05e1a11edec04091d

rework the ubus plugin to support JSON-RPC 2.0
---

diff --git a/CMakeLists.txt b/CMakeLists.txt
index 7273df6..d7712e4 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -2,7 +2,7 @@ cmake_minimum_required(VERSION 2.6)
 
 PROJECT(uhttpd C)
 SET(CMAKE_SHARED_LIBRARY_LINK_C_FLAGS "")
-ADD_DEFINITIONS(-Os -Wall -Werror -Wmissing-declarations --std=gnu99 -g3)
+ADD_DEFINITIONS(-O0 -Wall -Werror -Wmissing-declarations --std=gnu99 -g3)
 
 OPTION(TLS_SUPPORT "TLS support" ON)
 OPTION(LUA_SUPPORT "Lua support" ON)
diff --git a/session-test.sh b/session-test.sh
index 4d767f1..d569d53 100755
--- a/session-test.sh
+++ b/session-test.sh
@@ -17,4 +17,36 @@ json_close_array
 ubus call session grant "$(json_dump)"
 
 echo "Session: $sid"
-wget -O- "http://localhost:8080/ubus/$sid/session/list"
+echo "Request 1"
+wget -q -O- \
+	--post-data='{
+		"jsonrpc": "2.0",
+		"method" : "call",
+		"params" : [
+			"session",
+			"test",
+			{},
+		]
+	}' "http://localhost:8080/ubus/$sid/session/list"
+echo "Request 2"
+wget -q -O- \
+	--post-data='[
+	{
+		"jsonrpc": "2.0",
+		"method" : "call",
+		"params" : [
+			"session",
+			"list",
+			{},
+		]
+	},
+	{
+		"jsonrpc": "2.0",
+		"method" : "call",
+		"params" : [
+			"session",
+			"test",
+			{},
+		]
+	},
+	]' "http://localhost:8080/ubus/$sid/session/list"
diff --git a/ubus.c b/ubus.c
index 015b571..5230270 100644
--- a/ubus.c
+++ b/ubus.c
@@ -38,52 +38,130 @@ static struct blob_buf buf;
 
 #define UH_UBUS_MAX_POST_SIZE	4096
 
-static char *split_str(char *str)
+enum {
+	RPC_JSONRPC,
+	RPC_METHOD,
+	RPC_PARAMS,
+	RPC_ID,
+	__RPC_MAX,
+};
+
+static const struct blobmsg_policy rpc_policy[__RPC_MAX] = {
+	[RPC_JSONRPC] = { .name = "jsonrpc", .type = BLOBMSG_TYPE_STRING },
+	[RPC_METHOD] = { .name = "method", .type = BLOBMSG_TYPE_STRING },
+	[RPC_PARAMS] = { .name = "params", .type = BLOBMSG_TYPE_ARRAY },
+	[RPC_ID] = { .name = "id", .type = BLOBMSG_TYPE_UNSPEC },
+};
+
+struct rpc_data {
+	struct blob_attr *id;
+	const char *method;
+	const char *object;
+	const char *function;
+	struct blob_attr *data;
+};
+
+enum rpc_error {
+	ERROR_PARSE,
+	ERROR_REQUEST,
+	ERROR_METHOD,
+	ERROR_PARAMS,
+	ERROR_INTERNAL,
+	ERROR_OBJECT,
+	ERROR_SESSION,
+	ERROR_ACCESS,
+	ERROR_TIMEOUT,
+	__ERROR_MAX
+};
+
+static const struct {
+	int code;
+	const char *msg;
+} json_errors[__ERROR_MAX] = {
+	[ERROR_PARSE] = { -32700, "Parse error" },
+	[ERROR_REQUEST] = { -32600, "Invalid request" },
+	[ERROR_METHOD] = { -32601, "Method not found" },
+	[ERROR_PARAMS] = { -32602, "Invalid parameters" },
+	[ERROR_INTERNAL] = { -32603, "Internal error" },
+	[ERROR_OBJECT] = { -32000, "Object not found" },
+	[ERROR_SESSION] = { -32001, "Session not found" },
+	[ERROR_ACCESS] = { -32002, "Access denied" },
+	[ERROR_TIMEOUT] = { -32003, "ubus request timed out" },
+};
+
+static void __uh_ubus_next_batched_request(struct uloop_timeout *timeout);
+
+static void uh_ubus_next_batched_request(struct client *cl)
+{
+	struct dispatch_ubus *du = &cl->dispatch.ubus;
+
+	du->timeout.cb = __uh_ubus_next_batched_request;
+	uloop_timeout_set(&du->timeout, 1);
+}
+
+static void uh_ubus_send_header(struct client *cl)
+{
+	ops->http_header(cl, 200, "OK");
+	ustream_printf(cl->us, "Content-Type: application/json\r\n\r\n");
+}
+
+static void uh_ubus_send_response(struct client *cl)
 {
-	if (str)
-		str = strchr(str, '/');
+	struct dispatch_ubus *du = &cl->dispatch.ubus;
+	const char *sep = "";
+	char *str;
 
-	while (str && *str == '/') {
-		*str = 0;
-		str++;
+	if (du->array && du->array_idx > 1)
+		sep = ", ";
+
+	str = blobmsg_format_json_indent(buf.head, true, du->array);
+	ops->chunk_printf(cl, "%s%s", sep, str);
+	free(str);
+
+	du->jsobj_cur = NULL;
+	if (du->array)
+		uh_ubus_next_batched_request(cl);
+	else {
+		ops->chunk_printf(cl, "\n");
+		return ops->request_done(cl);
 	}
-	return str;
 }
 
-static bool
-uh_ubus_request_parse_url(struct client *cl, char *url, char **sid, char **obj, char **fun)
+static void uh_ubus_init_response(struct client *cl)
 {
-	url += strlen(conf.ubus_prefix);
-	while (url && *url == '/')
-		url++;
+	struct dispatch_ubus *du = &cl->dispatch.ubus;
+	struct json_object *obj = du->jsobj_cur;
 
-	*sid = url;
+	blob_buf_init(&buf, 0);
+	blobmsg_add_string(&buf, "jsonrpc", "2.0");
 
-	url = split_str(url);
-	*obj = url;
+	if (obj)
+		obj = json_object_object_get(obj, "id");
 
-	url = split_str(url);
-	*fun = url;
+	if (obj)
+		blobmsg_add_json_element(&buf, "id", obj);
+	else
+		blobmsg_add_field(&buf, BLOBMSG_TYPE_UNSPEC, "id", NULL, 0);
+}
 
-	return *sid && *obj && *fun;
+static void uh_ubus_json_error(struct client *cl, enum rpc_error type)
+{
+	void *c;
+
+	uh_ubus_init_response(cl);
+	c = blobmsg_open_table(&buf, "error");
+	blobmsg_add_u32(&buf, "code", json_errors[type].code);
+	blobmsg_add_string(&buf, "message", json_errors[type].msg);
+	blobmsg_close_table(&buf, c);
+	uh_ubus_send_response(cl);
 }
 
 static void
 uh_ubus_request_data_cb(struct ubus_request *req, int type, struct blob_attr *msg)
 {
 	struct dispatch_ubus *du = container_of(req, struct dispatch_ubus, req);
-	struct client *cl = container_of(du, struct client, dispatch.ubus);
-	char *str;
 
-	if (!du->header_sent) {
-		ops->http_header(cl, 200, "OK");
-		ustream_printf(cl->us, "Content-Type: application/json\r\n\r\n");
-		du->header_sent = true;
-	}
-
-	str = blobmsg_format_json_indent(msg, true, 0);
-	ops->chunk_write(cl, str, strlen(str));
-	free(str);
+	blobmsg_add_field(&du->buf, BLOBMSG_TYPE_TABLE, "", blob_data(msg), blob_len(msg));
 }
 
 static void
@@ -91,11 +169,28 @@ uh_ubus_request_cb(struct ubus_request *req, int ret)
 {
 	struct dispatch_ubus *du = container_of(req, struct dispatch_ubus, req);
 	struct client *cl = container_of(du, struct client, dispatch.ubus);
+	struct blob_attr *cur;
+	void *r;
+	int rem;
+
+	uloop_timeout_cancel(&du->timeout);
+	uh_ubus_init_response(cl);
+	r = blobmsg_open_array(&buf, "result");
+	blobmsg_add_u32(&buf, "", ret);
+	blob_for_each_attr(cur, du->buf.head, rem)
+		blobmsg_add_blob(&buf, cur);
+	blobmsg_close_array(&buf, r);
+	uh_ubus_send_response(cl);
+}
 
-	if (!du->header_sent)
-		return ops->client_error(cl, 204, "No content", "Function did not return data");
+static void
+uh_ubus_timeout_cb(struct uloop_timeout *timeout)
+{
+	struct dispatch_ubus *du = container_of(timeout, struct dispatch_ubus, timeout);
+	struct client *cl = container_of(du, struct client, dispatch.ubus);
 
-	ops->request_done(cl);
+	ubus_abort_request(ctx, &du->req);
+	uh_ubus_json_error(cl, ERROR_TIMEOUT);
 }
 
 static void uh_ubus_close_fds(struct client *cl)
@@ -111,6 +206,9 @@ static void uh_ubus_request_free(struct client *cl)
 {
 	struct dispatch_ubus *du = &cl->dispatch.ubus;
 
+	blob_buf_free(&du->buf);
+	uloop_timeout_cancel(&cl->timeout);
+
 	if (du->jsobj)
 		json_object_put(du->jsobj);
 
@@ -121,9 +219,11 @@ static void uh_ubus_request_free(struct client *cl)
 		ubus_abort_request(ctx, &du->req);
 }
 
-static void uh_ubus_json_error(struct client *cl)
+static void uh_ubus_single_error(struct client *cl, enum rpc_error type)
 {
-	ops->client_error(cl, 400, "Bad Request", "Invalid JSON data");
+	uh_ubus_send_header(cl);
+	uh_ubus_json_error(cl, type);
+	ops->request_done(cl);
 }
 
 static void uh_ubus_send_request(struct client *cl, json_object *obj)
@@ -132,94 +232,203 @@ static void uh_ubus_send_request(struct client *cl, json_object *obj)
 	struct dispatch_ubus *du = &d->ubus;
 	int ret;
 
-	blob_buf_init(&buf, 0);
-
-	if (obj && !blobmsg_add_object(&buf, obj))
-		return uh_ubus_json_error(cl);
-
+	blob_buf_init(&du->buf, 0);
+	memset(&du->req, 0, sizeof(du->req));
 	ret = ubus_invoke_async(ctx, du->obj, du->func, buf.head, &du->req);
 	if (ret)
-		return ops->client_error(cl, 500, "Internal Error",
-			"Error sending ubus request: %s", ubus_strerror(ret));
+		return uh_ubus_json_error(cl, ERROR_INTERNAL);
 
 	du->req.data_cb = uh_ubus_request_data_cb;
 	du->req.complete_cb = uh_ubus_request_cb;
 	ubus_complete_request_async(ctx, &du->req);
 
+	du->timeout.cb = uh_ubus_timeout_cb;
+	uloop_timeout_set(&du->timeout, conf.script_timeout);
+
 	du->req_pending = true;
 }
 
-static void uh_ubus_data_done(struct client *cl)
+static bool parse_json_rpc(struct rpc_data *d, struct blob_attr *data)
+{
+	const struct blobmsg_policy data_policy[] = {
+		{ .type = BLOBMSG_TYPE_STRING },
+		{ .type = BLOBMSG_TYPE_STRING },
+		{ .type = BLOBMSG_TYPE_TABLE },
+	};
+	struct blob_attr *tb[__RPC_MAX];
+	struct blob_attr *tb2[3];
+	struct blob_attr *cur;
+
+	blobmsg_parse(rpc_policy, __RPC_MAX, tb, blob_data(data), blob_len(data));
+
+	cur = tb[RPC_JSONRPC];
+	if (!cur || strcmp(blobmsg_data(cur), "2.0") != 0)
+		return false;
+
+	cur = tb[RPC_METHOD];
+	if (!cur)
+		return false;
+
+	d->id = tb[RPC_ID];
+	d->method = blobmsg_data(cur);
+
+	cur = tb[RPC_PARAMS];
+	if (!cur)
+		return false;
+
+	blobmsg_parse_array(data_policy, ARRAY_SIZE(data_policy), tb2,
+			    blobmsg_data(cur), blobmsg_data_len(cur));
+
+	if (!tb2[0] || !tb2[1] || !tb2[2])
+		return false;
+
+	d->object = blobmsg_data(tb2[0]);
+	d->function = blobmsg_data(tb2[1]);
+	d->data = tb2[2];
+	return true;
+}
+
+static void uh_ubus_init_batch(struct client *cl)
 {
 	struct dispatch_ubus *du = &cl->dispatch.ubus;
-	struct json_object *obj = du->jsobj;
 
-	if (!obj || json_object_get_type(obj) != json_type_object)
-		return uh_ubus_json_error(cl);
+	du->array = true;
+	uh_ubus_send_header(cl);
+	ops->chunk_printf(cl, "[\n\t");
+}
 
-	uh_ubus_send_request(cl, obj);
+static void uh_ubus_complete_batch(struct client *cl)
+{
+	ops->chunk_printf(cl, "\n]\n");
+	ops->request_done(cl);
 }
 
-static int uh_ubus_data_send(struct client *cl, const char *data, int len)
+static void uh_ubus_handle_request_object(struct client *cl, struct json_object *obj)
 {
 	struct dispatch_ubus *du = &cl->dispatch.ubus;
+	struct uh_ubus_session *ses;
+	struct rpc_data data = {};
+	enum rpc_error err = ERROR_PARSE;
 
-	if (du->jsobj) {
-		uh_ubus_json_error(cl);
-		return 0;
+	if (json_object_get_type(obj) != json_type_object)
+		goto error;
+
+	du->jsobj_cur = obj;
+	blob_buf_init(&buf, 0);
+	if (!blobmsg_add_object(&buf, obj))
+		goto error;
+
+	if (!parse_json_rpc(&data, buf.head))
+		goto error;
+
+	if (strcmp(data.method, "call") != 0) {
+		err = ERROR_METHOD;
+		goto error;
 	}
 
-	du->post_len += len;
-	if (du->post_len > UH_UBUS_MAX_POST_SIZE) {
-		ops->client_error(cl, 413, "Too Large", "Message too big");
-		return 0;
+	ses = uh_ubus_session_get(du->sid);
+	if (!ses) {
+		err = ERROR_SESSION;
+		goto error;
 	}
 
-	du->jsobj = json_tokener_parse_ex(du->jstok, data, len);
-	return len;
+	if (!uh_ubus_session_acl_allowed(ses, data.object, data.function)) {
+		err = ERROR_ACCESS;
+		goto error;
+	}
+
+	du->func = data.function;
+	if (ubus_lookup_id(ctx, data.object, &du->obj)) {
+		err = ERROR_OBJECT;
+		goto error;
+	}
+
+	uh_ubus_send_request(cl, obj);
+	return;
+
+error:
+	uh_ubus_json_error(cl, err);
 }
 
-static void uh_ubus_defer_post(struct client *cl)
+static void __uh_ubus_next_batched_request(struct uloop_timeout *timeout)
 {
-	struct dispatch *d = &cl->dispatch;
+	struct dispatch_ubus *du = container_of(timeout, struct dispatch_ubus, timeout);
+	struct client *cl = container_of(du, struct client, dispatch.ubus);
+	struct json_object *obj = du->jsobj;
+	int len;
 
-	d->ubus.jstok = json_tokener_new();
-	if (d->ubus.jstok)
-		return ops->client_error(cl, 500, "Internal Error", "Internal Error");
+	len = json_object_array_length(obj);
+	if (du->array_idx >= len)
+		return uh_ubus_complete_batch(cl);
 
-	d->data_send = uh_ubus_data_send;
-	d->data_done = uh_ubus_data_done;
+	obj = json_object_array_get_idx(obj, du->array_idx++);
+	uh_ubus_handle_request_object(cl, obj);
+}
+
+static void uh_ubus_data_done(struct client *cl)
+{
+	struct dispatch_ubus *du = &cl->dispatch.ubus;
+	struct json_object *obj = du->jsobj;
+
+	switch (obj ? json_object_get_type(obj) : json_type_null) {
+	case json_type_object:
+		uh_ubus_send_header(cl);
+		return uh_ubus_handle_request_object(cl, obj);
+	case json_type_array:
+		uh_ubus_init_batch(cl);
+		if (json_object_array_length(obj) > 0)
+			return uh_ubus_next_batched_request(cl);
+		/* fall through */
+	default:
+		return uh_ubus_single_error(cl, ERROR_PARSE);
+	}
+}
+
+static int uh_ubus_data_send(struct client *cl, const char *data, int len)
+{
+	struct dispatch_ubus *du = &cl->dispatch.ubus;
+
+	if (du->jsobj || !du->jstok)
+		goto error;
+
+	du->post_len += len;
+	if (du->post_len > UH_UBUS_MAX_POST_SIZE)
+		goto error;
+
+	du->jsobj = json_tokener_parse_ex(du->jstok, data, len);
+	return len;
+
+error:
+	uh_ubus_single_error(cl, ERROR_PARSE);
+	return 0;
 }
 
 static void uh_ubus_handle_request(struct client *cl, char *url, struct path_info *pi)
 {
-	struct uh_ubus_session *ses;
 	struct dispatch *d = &cl->dispatch;
-	char *sid, *obj, *fun;
+	char *sid, *sep;
 
 	blob_buf_init(&buf, 0);
 
-	if (!uh_ubus_request_parse_url(cl, url, &sid, &obj, &fun))
-		return ops->client_error(cl, 400, "Bad Request", "Invalid Request");
-
-	ses = uh_ubus_session_get(sid);
-	if (!ses)
-		return ops->client_error(cl, 404, "Not Found", "No such session %s", sid);
+	url += strlen(conf.ubus_prefix);
+	while (*url == '/')
+		url++;
 
-	if (!uh_ubus_session_acl_allowed(ses, obj, fun))
-		return ops->client_error(cl, 403, "Denied", "Access to object denied");
+	sep = strchr(url, '/');
+	if (sep)
+		*sep = 0;
 
-	if (ubus_lookup_id(ctx, obj, &d->ubus.obj))
-		return ops->client_error(cl, 500, "Not Found", "No such object");
+	sid = url;
+	if (strlen(sid) != 32 ||
+	    cl->request.method != UH_HTTP_MSG_POST)
+		return ops->client_error(cl, 400, "Bad Request", "Invalid Request");
 
 	d->close_fds = uh_ubus_close_fds;
 	d->free = uh_ubus_request_free;
-	d->ubus.func = fun;
-
-	if (cl->request.method == UH_HTTP_MSG_POST)
-		uh_ubus_defer_post(cl);
-	else
-		uh_ubus_send_request(cl, NULL);
+	d->data_send = uh_ubus_data_send;
+	d->data_done = uh_ubus_data_done;
+	d->ubus.jstok = json_tokener_new();
+	d->ubus.sid = sid;
 }
 
 static bool
diff --git a/uhttpd.h b/uhttpd.h
index 590d486..12cfc28 100644
--- a/uhttpd.h
+++ b/uhttpd.h
@@ -160,13 +160,21 @@ struct dispatch_handler {
 #ifdef HAVE_UBUS
 struct dispatch_ubus {
 	struct ubus_request req;
+
+	struct uloop_timeout timeout;
 	struct json_tokener *jstok;
 	struct json_object *jsobj;
-	uint32_t obj;
+	struct json_object *jsobj_cur;
 	int post_len;
+
+	const char *sid;
+	uint32_t obj;
 	const char *func;
+
+	struct blob_buf buf;
 	bool req_pending;
-	bool header_sent;
+	bool array;
+	int array_idx;
 };
 #endif